Added sha256 functions

1 files changed, 127 insertions, 0 deletions

diff --git a/src/sha256/sha256.cpp b/src/sha256/sha256.cpp
new file mode 100644
index 0000000..3feded9
--- /dev/null
+++ b/src/sha256/sha256.cpp
@@ -0,0 +1,127 @@
+#include <cstring>
+#include <fstream>
+#include "sha256.h"
+
+const unsigned int SHA256::sha256_k[64] = //UL = uint32
+        {0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5,
+         0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5,
+         0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3,
+         0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174,
+         0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc,
+         0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
+         0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7,
+         0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967,
+         0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13,
+         0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
+         0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3,
+         0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
+         0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5,
+         0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
+         0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208,
+         0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2};
+
+void SHA256::transform(const unsigned char *message, unsigned int block_nb) {
+    uint32 w[64];
+    uint32 wv[8];
+    uint32 t1, t2;
+    const unsigned char *sub_block;
+    int i;
+    int j;
+    for (i = 0; i < (int) block_nb; i++) {
+        sub_block = message + (i << 6);
+        for (j = 0; j < 16; j++) {
+            SHA2_PACK32(&sub_block[j << 2], &w[j]);
+        }
+        for (j = 16; j < 64; j++) {
+            w[j] = SHA256_F4(w[j - 2]) + w[j - 7] + SHA256_F3(w[j - 15]) + w[j - 16];
+        }
+        for (j = 0; j < 8; j++) {
+            wv[j] = m_h[j];
+        }
+        for (j = 0; j < 64; j++) {
+            t1 = wv[7] + SHA256_F2(wv[4]) + SHA2_CH(wv[4], wv[5], wv[6])
+                 + sha256_k[j] + w[j];
+            t2 = SHA256_F1(wv[0]) + SHA2_MAJ(wv[0], wv[1], wv[2]);
+            wv[7] = wv[6];
+            wv[6] = wv[5];
+            wv[5] = wv[4];
+            wv[4] = wv[3] + t1;
+            wv[3] = wv[2];
+            wv[2] = wv[1];
+            wv[1] = wv[0];
+            wv[0] = t1 + t2;
+        }
+        for (j = 0; j < 8; j++) {
+            m_h[j] += wv[j];
+        }
+    }
+}
+
+void SHA256::init() {
+    m_h[0] = 0x6a09e667;
+    m_h[1] = 0xbb67ae85;
+    m_h[2] = 0x3c6ef372;
+    m_h[3] = 0xa54ff53a;
+    m_h[4] = 0x510e527f;
+    m_h[5] = 0x9b05688c;
+    m_h[6] = 0x1f83d9ab;
+    m_h[7] = 0x5be0cd19;
+    m_len = 0;
+    m_tot_len = 0;
+}
+
+void SHA256::update(const unsigned char *message, unsigned int len) {
+    unsigned int block_nb;
+    unsigned int new_len, rem_len, tmp_len;
+    const unsigned char *shifted_message;
+    tmp_len = SHA224_256_BLOCK_SIZE - m_len;
+    rem_len = len < tmp_len ? len : tmp_len;
+    memcpy(&m_block[m_len], message, rem_len);
+    if (m_len + len < SHA224_256_BLOCK_SIZE) {
+        m_len += len;
+        return;
+    }
+    new_len = len - rem_len;
+    block_nb = new_len / SHA224_256_BLOCK_SIZE;
+    shifted_message = message + rem_len;
+    transform(m_block, 1);
+    transform(shifted_message, block_nb);
+    rem_len = new_len % SHA224_256_BLOCK_SIZE;
+    memcpy(m_block, &shifted_message[block_nb << 6], rem_len);
+    m_len = rem_len;
+    m_tot_len += (block_nb + 1) << 6;
+}
+
+void SHA256::final(unsigned char *digest) {
+    unsigned int block_nb;
+    unsigned int pm_len;
+    unsigned int len_b;
+    int i;
+    block_nb = (1 + ((SHA224_256_BLOCK_SIZE - 9)
+                     < (m_len % SHA224_256_BLOCK_SIZE)));
+    len_b = (m_tot_len + m_len) << 3;
+    pm_len = block_nb << 6;
+    memset(m_block + m_len, 0, pm_len - m_len);
+    m_block[m_len] = 0x80;
+    SHA2_UNPACK32(len_b, m_block + pm_len - 4);
+    transform(m_block, block_nb);
+    for (i = 0; i < 8; i++) {
+        SHA2_UNPACK32(m_h[i], &digest[i << 2]);
+    }
+}
+
+std::string sha256(std::string input) {
+    unsigned char digest[SHA256::DIGEST_SIZE];
+    memset(digest, 0, SHA256::DIGEST_SIZE);
+
+    SHA256 ctx = SHA256();
+    ctx.init();
+    ctx.update((unsigned char *) input.c_str(), input.length());
+    ctx.final(digest);
+
+    char buf[2 * SHA256::DIGEST_SIZE + 1];
+    buf[2 * SHA256::DIGEST_SIZE] = 0;
+    for (int i = 0; i < SHA256::DIGEST_SIZE; i++)
+        sprintf(buf + i * 2, "%02x", digest[i]);
+    return std::string(buf);
+}
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